Change object.color property of multiple objects at a time without scripting?
The ALT multiple-property editing mechanic does not work if you click directly the Color Wheel, however it does work if you're tweaking the Red, Green or Blue channels of the color.
Note that you will have to set the display to RGB instead of the default HSV beforehand. It does not matter if you press ALT when clicking on the color field, but you do have to press it when scrubbing or before inputting a value in one of the channels.
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Also note that if you are scrubbing a channel field, the value of that channel in all the selected objects will get relatively incremented by the scrubbed value, but if they start with a different color, their color won't always match when you finish scrubbing.
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